Evaluating navy beans as a source of high quality/value protein ingredients

Growing interest in plant proteins as replacements for animal proteins is driven by consumers’ awareness of health benefits, shifts in their diets, and environmental concerns. Among the plant protein sources, legumes like navy beans stand out as excellent sources of protein. Navy beans are easy to cultivate, offer environmental benefits, and fit well within crop rotations. However, the utilization of navy beans and other dry beans has traditionally been limited to canned and whole dry bean products. This study aimed to expand the applications of this underutilized crop by developing an optimized process for the production of navy bean protein isolate (NBPI). Two varieties of navy beans, each grown in two different locations, were evaluated for protein structural functional characteristics. To identify the optimal solubilization pH for protein extraction, a pH range of 7 to 10 was tested. A high protein purity (79.2–80.7%) and yield (60–64.4%) were observed at a solubilization pH of 7.5.  As observed by SDS-PAGE, NBPI exhibited prominent protein bands around 48–52 kDa, which was identified as vicilin subunits. Regardless of the cultivar, NBPI exhibited high protein solubility (~88–95%) at neutral pH, similar to soy protein and better than pea protein. In contrast, variations in surface hydrophobicity and gel strength (16-22 N) were influenced by both cultivar and growing location, which also affected emulsification capacity (625-805 mL oil/g protein). Both gelation and emulsification properties were comparable to or better than soy and pea protein, respectively. The current study contributed to a better understanding of the effects of genotype and environment on a wide range of properties of navy bean proteins. In addition, results demonstrated that navy beans are a viable source of functional protein for incorporation into various food products.